1. Field of the Invention
The present invention pertains to an apparatus and method for applying a pharmaceutical to the tympanic membrane in preparation for performing a photodynamic laser myringotomy. In particular, the present invention pertains to a packaged kit that includes a plurality of ear needles having different shaped absorbent applicators on distal ends of the needles, a vial of a single dose of an otologic formulation of mitomycin-C, a diluent carrier containing sterilized water, and a syringe. The component parts of the apparatus are used together to reconstitute the contents of the vial with the water in the diluent carrier, and then draw the reconstituted drug into the syringe. A selected one of the plurality of ear needles is then communicated with the syringe. The syringe and needle are then used to inject the reconstituted drug into the absorbent pad at the end of the needle, and use the absorbent pad containing the drug to apply the drug to the tympanic membrane. The application of the drug to the tympanic membrane prepares the membrane for a myringotomy procedure, and in particular, a photodynamic laser myringotomy.
2. Description of the Related Art
A myringotomy, which is a surgical puncture of the ear tympanic membrane or ear drum, is the most often performed procedure for relieving recurrent acute otitis media (RAOM), or recurrent ear infections resulting from fluid build-up in the middle ear. Recurrent acute otitis media is the most common reason for children's visits to physicians and results in more than 600,000 myringotomy procedures annually in the United States alone. Myringotomy is the single-most common surgical procedure performed on patients under the age of 15.
However, myringotomy alone often will not result in the sustained relief of the infection. In order to relieve the infection, the opening in the ear drum that allows for the fluid drainage must remain open for an extended period of time. This allows for ventilation of the ear canal and the resolution of the infection. The myringotomy opening through the ear drum is kept open by the implantation of a pressure equalization tube in the ear drum. The insertion of the tube through the ear drum allows drainage of the fluid in the middle ear that is the source of the ear infection. The ear tube is typically a small plastic tube having a spool shape. While this is not a perfect solution, inserting the pressure equalization tube through the ear drum most often achieves the desired clinical objective, the resolution of the infection.
The tube insertion is a routine procedure, and typically requires only a few minutes of the physician's time. The tube insertion can be performed as an outpatient surgery. However, because the procedure is typically performed on a child, it is often necessary that the child be unconscious or under a general anesthesia in order to achieve the desired level of compliance from the child. The need to anesthetize the child transforms what would be a very simple clinical procedure into a fully involved surgical procedure. It would be very desirable to remove the anesthesia requirement from the myringotomy procedure. With the removal of the anesthesia requirement, a myringotomy procedure could be performed by the physician at most any convenient location.
Myringotomies have been performed without the use of pressure equalization tubes. In these investigational myringotomy procedures, the physician uses a lance to produce an opening in the ear drum and also uses mitomycin-C to treat the ear drum in the area of the lance insertion. Mitomycin-C is an anti-metabolic agent that acts by interrupting DNA synthesis. It has been used as a chemotherapy agent, for example, in stomach and pancreatic cancers, for many years. Its anti-metabolic properties have prompted ophthalmologists to consider its use as a means of improving patency in trabeculectomy surgery. This procedure is well suited for the use of mitomycin, and the use of mitomycin in the procedure has ultimately become a standard of physicians.
The successful fistulae formation in glaucoma surgery with the accompanying use of mitomycin-C has resulted in experimentation in a variety of different surgical procedures where the desired end point, a functional, patent fistulae, is the same. Most notable among these procedures is the myringotomy procedure, or the surgical creation of a pathway through the tympanic membrane.
A myringotomy performed with a lance and the concomitant use of mitomycin-C has been demonstrated to provide a statistically significant increase in the time required for closure of the fistulae formed, versus a myringotomy procedure performed without the benefit of the accompanying use of mitomycin-C. It has been further demonstrated that the use of post-operative dexamethasone or an equivalent anti-inflammatory agent has further improved these results, providing data functionally equivalent to that of a myringotomy procedure performed with pressure equalization tube insertion.
The use of a laser for performance of a myringotomy procedure is also well understood. However, the use of a laser alone in the procedure is generally viewed as inefficient in the treatment of recurrent acute otitis media, or ear infections due to fluid build-up in the middle ear, because the laser opening in the ear drum will not remain open long enough to achieve the desired clinical end point.
While the procedures discussed above eliminate the use of the pressure equalization tubes typically employed in myringotomy procedures, they do not address the critical issue of patient compliance and the resultant need for anesthesia when performing a myringotomy procedure on a child.